Russian technology waves goodbye to strained silicon

A Welsh start-up has linked with Russian technologists to develop a transistor architecture that could go against strained silicon as a way of boosting transistor performance without forcing the industry to move to much smaller devices.

Monmouth-based Sceptre Electronic has unveiled an approach that gets the boost by using transistor channels that are doped periodically, not all the way along.

According to the company, the periodic doping boosts the mobility of charge carriers in the transistor and, as a result, increases the operating frequency.

To produce the channels, the company developed a method of doping silicon with a lateral period of between 20 and 100nm. The running ion beam (RIB) process produces wave-ordered structures, which act as a nano-sized mask for molecular self-formation.

Leon Rizzi, co-founder of Sceptre, said: "We have been working with the Russian Institute for Microelectronics on this process for several years. RIB, which uses a modi-fied ion chamber, replaces litho-graphy with molecular self-formation."

The process, which can be integrated into conventional MOS technology, has surpassed expectations, says Rizzi.

"We can build profiles down to 8nm without masks," he said.

Sceptre's technology offers an alternative route to strained silicon, which stretches the lattice of a layer of silicon to conform to a layer of silicon germanium below, resulting in faster electron flow.

Another Welsh company, IQE, is set to become the world's first merchant manufacturer of strained silicon wafers.

Rizzi says that papers on the RIB process, which is capable of treating between 36 and 38 wafers an hour, will go through peer review this summer.

"There's only one problem," said Rizzi. "The process was developed in Russia so people don't believe you until you've proved it 10 times over."